Passing garbage as C++ arguments

compilation.txt

$ clang++ -Wall -Werror -framework Foundation -std=c++11 -stdlib=libc++ garbage.mm -o test && ./test && echo $?
0 // MyClass didn't get initialized?
0 // method calls don't fail either
0 // exit code. No Crash?

garbage.mm

#import <Foundation/Foundation.h>
#import <iostream>

using namespace std;

class MyClass
{
public:
    MyClass() : a(3) {}

    int getA() const { return a; }

    static void print(const MyClass &c)
    {
        cout << c.a << endl; // prints 0
	cout << c.getA() << endl; // doesn't crash, and prints 0
    }

    const int a;
};

@interface A : NSObject

- (MyClass)someMethod;

@end

@implementation A

- (MyClass)someMethod
{
    return MyClass();
}

@end

int main(int argc, const char * argv[])
{
    @autoreleasepool {
        A *a = nil;
	
        MyClass::print([a someMethod]);
    }

    return 0;
}